1. Field of the Invention
This invention relates to improvements in the control of exercise machines utilizing interval training based on detecting a user's heart rate.
2. Description of the Related Art
The monitoring of heart rates for use on exercise equipment of all kinds, vertical bicycles, recumbent bicycles, steppers, treadmills, rowing machines and the like is well known. Typically, the exercise rate of the user is maintained according to a preset or calculated heart rate. The heart rate often is set based upon the user's age, weight and sex.
The user begins the exercise cycle by entering a warm-up period for a predetermined amount of time during which the exercise rate is not controlled by the actual monitored heart rate, other than perhaps a maximum limit. After the warm-up period, the user then increases the exercise rate or load, while the heart rate is monitored. The load may be varied according to various types of algorithms as the target heart rate is approached. Once the target heart rate is achieved, the load is thereafter varied to maintain the heart rate for a predetermined time or amount of exercise. Thereafter, a cool-down exercise period is performed at lower exercise rates or loads during which the heart rate is allowed to decrease.
However, it is appreciated by athletes that physical fitness training is more effectively reached by interval training. Interval training can, in general, be described as exercise at periodically higher and lower rates in a cyclic or repetitive pattern so that physical endurance is built up. Such interval training is based upon a cyclic pattern of physical exercise rates or exercise loads without regard to cardiopulmonary function, but is more directly concerned with the exercise and strengthening of skeletal muscle.